Question

An experiment was conducted to compare the range of two types of wireless headsets. Independent random samples of comparable Sony and Beats by Dre headsets were obtained, and the range of each was tested and measured (in meters).

subject: 1 2 3 4 5

B: Before 192 210 206 200 192

A: After 172 81 198 195 193

Assuming normality, construct a 98% confidence interval for the true difference in mean range between the two headsets to determine if a difference exists. (16 points) (1) (2) Sony Beats by Dre Sample Mean 9.007 9.144 Sample Standard Deviation 0.518 0.630 Sample Size 13 12 Assumptions:__________________________________ _____________________________________________ _____________________________________________ _____________________________________________ _____________________________________________ _____________________________________________

Reliability Coefficient___________________________ (____________________________________________)

Ho:___________________________________________

Ha:___________________________________________

Conclusion:____________________________________ _____________________________________________ _____________________________________________ ___________________________________________

Answer 1

Assumptions:

The dependent variable must be continuous (interval/ratio).

The observations are independent of one another.

The dependent variable should be approximately normally distributed.

The dependent variable should not contain any outliers.

The 98% confidence interval for the true difference in mean range between the two headsets to determine if a difference exists is between -59.377 and 123.777.

Before	After	d
192	172	20
210	81	129
206	198	8
200	195	5
192	193	-1
	200.000	mean Before
	167.800	mean After
	32.200	mean difference (Before - After)
	54.651	std. dev.
	24.441	std. error
	5	n
	4	df
	-59.377	confidence interval 98.% lower
	123.777	confidence interval 98.% upper
	91.577	margin of error